Coastal Engineering Significance . UNNA (1942) is the oldest paper in- 

 cluded in the annotated bibliography. It is included solely for histo- 

 rical reasons. Observations of wave-current interaction, especially in 

 tide races, are familiar to many navigators and are briefly mentioned by 

 Rayleigh (1911), but no attempt to analyze the interaction has been 

 found to predate this paper. 



58. VINCENT, C.E., "The Interaction of Wind-Generated Sea Waves with 

 Tidal Currents," Journal of Physical Oceanography, Vol. 9, No. 4, 

 July 1979, pp. 748-755. 



Keywords. Comparison of Theory and Measurement; Currents, Large-Scale; 

 Currents, Tidal; Fetch; Observation; Wave Height; Waves, Wind. 



Discussion. A relatively simple one-dimensional theory is given for 

 waves propagating upon a tidal stream. Results are given for the cases 

 where the tide is just a propagating long wave and where it includes a 

 component propagating in the opposite direction, e.g., where the tide is 

 a standing wave. 



The 16-day periods of wave records from gas production platforms on 

 the North Sea were analyzed. These showed wave heights to be modulated 

 with a tidal period. The tides were modeled by a simple expression of 

 the above type and the theoretical wave modulation was estimated and 

 compared with observation. Good correspondence was found with the phase 

 of the modulations, but the actual amplitude of the modulations was much 

 larger than estimated. 



A discussion of the limitations of the approach includes mention of 

 the true tidal current field and depth refraction of the waves. 



Coastal Engineering Significance. Field data at the North Sea platforms 

 show that height is affected by tidal currents, and the observed height 

 is higher than predicted by the simple theory used. The data shows the 

 type of height variation to be expected in areas with significant tidal 

 currents . 



59. WHITHAM, G.B., "Mass Momentum and Energy Flux in Water Waves," 

 Journal of Fluid Mechanics , Cambridge, England, Vol. 12, No. 1, 

 Jan. 1962, pp. 135-147. 



Keywords. Averaged Equations; Conservation Equations; Currents, 

 Unidirectional; Equations of Motion; Group Velocity; Wave Effect on 

 Current; Wave Energy; Waves, Finite-Amplitude. 



Discussion. It is noted that the energy of a current with waves upon it 

 cannot be uniquely divided into wave energy and current energy. The 

 energy equation can be modified in a consistent manner by subtracting 



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